Fix upgrade logic which was not detecting upgrades properly, due to decorator.
Fix upgrade logic which was not detecting upgrades properly, due to decorator.

indirectlylit/kolibri,mrpau/kolibri,indirectlylit/kolibri,mrpau/kolibri,learningequality/kolibri,learningequality/kolibri,learningequality/kolibri,indirectlylit/kolibri,mrpau/kolibri,mrpau/kolibri,learningequality/kolibri,indirectlylit/kolibri